[PATCH 5.10 287/406] scsi: mpt3sas: Perform additional retries if doorbell read returns 0

Greg Kroah-Hartman
2023-09-17T19:36:59Z

From: Ranjan Kumar <ranjan.kumar@broadcom.com>

commit 4ca10f3e31745d35249a727ecd108eb58f0a8c5e upstream.

The driver retries certain register reads 3 times if the returned value is
0. This was done because the controller could return 0 for certain
registers if other registers were being accessed concurrently by the BMC.

In certain systems with increased BMC interactions, the register values
returned can be 0 for longer than 3 retries. Change the retry count from 3
to 30 for the affected registers to prevent problems with out-of-band
management.

Fixes: b899202901a8 ("scsi: mpt3sas: Add separate function for aero doorbell reads")
Cc: stable@vger.kernel.org
Signed-off-by: Ranjan Kumar <ranjan.kumar@broadcom.com>
Link: https://lore.kernel.org/r/20230829090020.5417-2-ranjan.kumar@broadcom.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/scsi/mpt3sas/mpt3sas_base.c | 46 +++++++++++++++++++++++++-----------
drivers/scsi/mpt3sas/mpt3sas_base.h | 1
2 files changed, 34 insertions(+), 13 deletions(-)

--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -131,6 +131,9 @@ _base_get_ioc_facts(struct MPT3SAS_ADAPT
static void
_base_clear_outstanding_commands(struct MPT3SAS_ADAPTER *ioc);

+static u32
+_base_readl_ext_retry(const volatile void __iomem *addr);
+
/**
* mpt3sas_base_check_cmd_timeout - Function
* to check timeout and command termination due
@@ -206,6 +209,20 @@ _base_readl_aero(const volatile void __i
return ret_val;
}

+static u32
+_base_readl_ext_retry(const volatile void __iomem *addr)
+{
+ u32 i, ret_val;
+
+ for (i = 0 ; i < 30 ; i++) {
+ ret_val = readl(addr);
+ if (ret_val == 0)
+ continue;
+ }
+
+ return ret_val;
+}
+
static inline u32
_base_readl(const volatile void __iomem *addr)
{
@@ -861,7 +878,7 @@ mpt3sas_halt_firmware(struct MPT3SAS_ADA

dump_stack();

- doorbell = ioc->base_readl(&ioc->chip->Doorbell);
+ doorbell = ioc->base_readl_ext_retry(&ioc->chip->Doorbell);
if ((doorbell & MPI2_IOC_STATE_MASK) == MPI2_IOC_STATE_FAULT) {
mpt3sas_print_fault_code(ioc, doorbell &
MPI2_DOORBELL_DATA_MASK);
@@ -5667,7 +5684,7 @@ mpt3sas_base_get_iocstate(struct MPT3SAS
{
u32 s, sc;

- s = ioc->base_readl(&ioc->chip->Doorbell);
+ s = ioc->base_readl_ext_retry(&ioc->chip->Doorbell);
sc = s & MPI2_IOC_STATE_MASK;
return cooked ? sc : s;
}
@@ -5812,7 +5829,7 @@ _base_wait_for_doorbell_ack(struct MPT3S
__func__, count, timeout));
return 0;
} else if (int_status & MPI2_HIS_IOC2SYS_DB_STATUS) {
- doorbell = ioc->base_readl(&ioc->chip->Doorbell);
+ doorbell = ioc->base_readl_ext_retry(&ioc->chip->Doorbell);
if ((doorbell & MPI2_IOC_STATE_MASK) ==
MPI2_IOC_STATE_FAULT) {
mpt3sas_print_fault_code(ioc, doorbell);
@@ -5852,7 +5869,7 @@ _base_wait_for_doorbell_not_used(struct
count = 0;
cntdn = 1000 * timeout;
do {
- doorbell_reg = ioc->base_readl(&ioc->chip->Doorbell);
+ doorbell_reg = ioc->base_readl_ext_retry(&ioc->chip->Doorbell);
if (!(doorbell_reg & MPI2_DOORBELL_USED)) {
dhsprintk(ioc,
ioc_info(ioc, "%s: successful count(%d), timeout(%d)\n",
@@ -5989,7 +6006,7 @@ _base_handshake_req_reply_wait(struct MP
__le32 *mfp;

/* make sure doorbell is not in use */
- if ((ioc->base_readl(&ioc->chip->Doorbell) & MPI2_DOORBELL_USED)) {
+ if ((ioc->base_readl_ext_retry(&ioc->chip->Doorbell) & MPI2_DOORBELL_USED)) {
ioc_err(ioc, "doorbell is in use (line=%d)\n", __LINE__);
return -EFAULT;
}
@@ -6038,7 +6055,7 @@ _base_handshake_req_reply_wait(struct MP
}

/* read the first two 16-bits, it gives the total length of the reply */
- reply[0] = le16_to_cpu(ioc->base_readl(&ioc->chip->Doorbell)
+ reply[0] = le16_to_cpu(ioc->base_readl_ext_retry(&ioc->chip->Doorbell)
& MPI2_DOORBELL_DATA_MASK);
writel(0, &ioc->chip->HostInterruptStatus);
if ((_base_wait_for_doorbell_int(ioc, 5))) {
@@ -6046,7 +6063,7 @@ _base_handshake_req_reply_wait(struct MP
__LINE__);
return -EFAULT;
}
- reply[1] = le16_to_cpu(ioc->base_readl(&ioc->chip->Doorbell)
+ reply[1] = le16_to_cpu(ioc->base_readl_ext_retry(&ioc->chip->Doorbell)
& MPI2_DOORBELL_DATA_MASK);
writel(0, &ioc->chip->HostInterruptStatus);

@@ -6057,10 +6074,10 @@ _base_handshake_req_reply_wait(struct MP
return -EFAULT;
}
if (i >= reply_bytes/2) /* overflow case */
- ioc->base_readl(&ioc->chip->Doorbell);
+ ioc->base_readl_ext_retry(&ioc->chip->Doorbell);
else
reply[i] = le16_to_cpu(
- ioc->base_readl(&ioc->chip->Doorbell)
+ ioc->base_readl_ext_retry(&ioc->chip->Doorbell)
& MPI2_DOORBELL_DATA_MASK);
writel(0, &ioc->chip->HostInterruptStatus);
}
@@ -6906,7 +6923,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER
goto out;
}

- host_diagnostic = ioc->base_readl(&ioc->chip->HostDiagnostic);
+ host_diagnostic = ioc->base_readl_ext_retry(&ioc->chip->HostDiagnostic);
drsprintk(ioc,
ioc_info(ioc, "wrote magic sequence: count(%d), host_diagnostic(0x%08x)\n",
count, host_diagnostic));
@@ -6926,7 +6943,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER
for (count = 0; count < (300000000 /
MPI2_HARD_RESET_PCIE_SECOND_READ_DELAY_MICRO_SEC); count++) {

- host_diagnostic = ioc->base_readl(&ioc->chip->HostDiagnostic);
+ host_diagnostic = ioc->base_readl_ext_retry(&ioc->chip->HostDiagnostic);

if (host_diagnostic == 0xFFFFFFFF) {
ioc_info(ioc,
@@ -7313,10 +7330,13 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPT
ioc->rdpq_array_enable_assigned = 0;
ioc->use_32bit_dma = false;
ioc->dma_mask = 64;
- if (ioc->is_aero_ioc)
+ if (ioc->is_aero_ioc) {
ioc->base_readl = &_base_readl_aero;
- else
+ ioc->base_readl_ext_retry = &_base_readl_ext_retry;
+ } else {
ioc->base_readl = &_base_readl;
+ ioc->base_readl_ext_retry = &_base_readl;
+ }
r = mpt3sas_base_map_resources(ioc);
if (r)
goto out_free_resources;
--- a/drivers/scsi/mpt3sas/mpt3sas_base.h
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
@@ -1469,6 +1469,7 @@ struct MPT3SAS_ADAPTER {
u8 diag_trigger_active;
u8 atomic_desc_capable;
BASE_READ_REG base_readl;
+ BASE_READ_REG base_readl_ext_retry;
struct SL_WH_MASTER_TRIGGER_T diag_trigger_master;
struct SL_WH_EVENT_TRIGGERS_T diag_trigger_event;
struct SL_WH_SCSI_TRIGGERS_T diag_trigger_scsi;